Automatic apparatus for chemical treatment of metal articles in bulk



Aug. 26, 1958 H. JACKSON 2,849,097 AUTOMATIC APPARATUS FOR CHEMICALTREATMENT 0F METAL ARTICLES IN BULK 8 Sheets-Sheet 1 Filled Aug. 5, 1954Aug. 26, 1958 w. H. JACKSON 2,849,097

AUTOMATIC APPARATUS FOR CHEMICAL TREATMENT OF METAL ARTICLES 1N BULK 8Sheets-Sheet 2 Filed Aug. 5, 1954 t I uI l, 1

INVENTOR.

w. H. JACKSON ARATus Aug. 2s, 195s 2,849,097 AUTOMATIC APP FOR CHEMICALTREATMENT oF METAL ARTICLES IN BULK 8 Sheets-Sheet 3 Filed Aug. 5, 1954form/ZVS.

Aug. 26, 1958 W. H. JACKSON AUTOMATIC APPARATUS FOR CHEMICAL TREATMENTOF METAL ARTICLES IN BULK Filed Aug. 5, 1954 'a sheets-sheet 4 A118- 261958 w H. JACKSON 2,849,097

AUTOMATIC APPARATUS FCR CHEMICAL TREATMENT oF Filed Aug. 5. 1954 METALARTICLES IN BULK 8 Sheets-Sheet* 5 amv/1kg Aug. 26, 1958 w SON ,849,097

H. JAC AUTOMATIC APPARATUS FOR CHEMICAL TREATMENT OF METAL ARTICLES INBULK Filed Aug. 5, 1954 8 Sheets-Sheet 6 2'/ JNVENTOR.

/2/ JZCSO?? BY W/afgwf Aug. 2s, 1958 w s H. JACK ON AUTOMATIC APPARATUSFOR CHEMICAL. TREATMENT OF METAL ARTICLES IN BULK Filed Aug. 5, 1954 8Sheets-Sheet 7 A118- 26, 1958 w. H. JACKSON 2,849,097

AUTOMATIC APPARATUS FOR CHEMICAL TREATMENT OF METAL ARTICLES IN BULKFiled Aug. 5, 1954 8 Sheets-Sheet 8 United States Patent() AUTOMATICAPPARATUS FOR CHEMICAL TREATMENT F METAL ARTICLES IN BULK 1s claims.(cl. ias-19) The present invention relates generally to apparatus forthe plating or chemical treatment of metal articles, par-p` ticularlyarticles in bulk, that is, articles too small for, or

not economically capable of, individual handling. The.`

invention relates more specifically to an lautomatic Vmachine for thecleaning, preparation and plating or coating in bulk of large quantitiesof small articles such as bolts, 4

screws, springs, stampings, etc.

In the past, plating or coating in bulk has been carried out by placinga considerable number of small metal articles such as bolts, screws,Washers, etc. in a tumblingv barrel which is immersed in a plating orcoating solution. Likewise, the cleaning, pickling, washing and rinsingof such arti-cles preparatory to plating or coating have also p beencarried out in tumbling barrels immersed in thet various cleaning orpickling solutions. Most commercial operations have utilized individualpieces of apparatus for each of these operations and sometimes thesevarious pieces have been arranged close together in a `lay-out favoringmore or less intermittent 'flow of Work. Monorails or overhead cranesare then utilized `to advance a barrel or its contents from one treatingtank tothe next.

In such a layout, each tank is separately equipped with duplicate barrelrotating d rive and other accessories. However, the variousacid-pickling, washing, lrinsing and Various plating solutions ofnecessity require dilerent immersion times. Thus, between or about thevarious pieces of equipment, in such a typicalcommercial plant layout,there are usually provided work storage or holdup devices for storingWork from the faster operations. When this is done, damage to the workmay occur due to drag-out of :corrosive solutions ,or the corrosiveplating room atmosphere. Thus, a true vcontinuous operation in bulkplating has not been achieved to the same degree as in the plating ofthe type of work ,that can be individually suspended from continuousconveyor systems .and successively raised and lowered into and out of-the various treating baths.

In a similar fashion, 'the lapplication of chemical coat- 2,849,097Patented Aug. 26, 1958 ings and treatments such as phosphate and oXalatecoatings on metal articles in bulk have been conducted in rotatingbarrels. Continuous operation in this eld also has not been completelysatisfactory.

It is a principal object of this invention, therefore, to provide anautomatic machine for the complete preparation, cleaning, plating orcoating and post treatment of .articles iu bulk.

Another object of this invention is to provide a machine in which workflows from onetreating step to another without hold-up or storage.

Still another important object of this invention is to provide a platingor treating machine wherein the work is supported on individualcarriages, the work is lifted independently -of the carriages by anelevator rail, and `flow of Work is achieved by simultaneously advancingthe carriages while the work is supported on the elevator rail.

Still another object is to provide a bulk plating or treating machinewhich rotates the plating barrels in both lower and upper positions atthe respective processing tanks, this latter feature to cut downsolution dragout and undesirable action of such solutions. The equipmentprovided for this purpose comprises a lineshaft gearing and one or moreindividual motor drives opposite those stations requiring barrelrotation andan epieyclic gear train or power take-efr device on each ofa plurality of work-supporting carriage units for making contact withthe lineshaft or individual motor drives.

Still yanother object is to provide a continuous bulk plat- "ing ortreating machine wherein all drive mechanisms,

,for inspection, lubrication and maintenance.

Another further object of this invention is to provide a continuous bulkplating or treating machine capable of specication plating or coating athigh capacity with close quality control and which can be operated by asingle operator. v

Another object'of this invention lis 4to provide `an automatic bulkplating or treating machine which has the high capacity derived from theuse of the horizontal type of plating or treating barrel. The use of thehorizontal barrels in the apparatus of this invention is permitted bysuspending each barrel on a pantograph type suspension, supporting thepantograph suspension on individual carriages, and lifting thesuspensions and suspended barrels independently of the carriages.

A yet further object is to provide acontinuous machine V,which minimizesdrag-out and loss of poisonous and expensive plating and treatingsolutions by virtue of con tinued rotation of the barrel in a positionabove the treating solution, and where necessary, a delayed set-down oradvance lift-up device to reduce contact time and permit longer drainagetime.

It is also an object to provide a machine which is easily susceptible tomodification to provide a variety of barrel rotation speeds as requiredby the nature of the plating or treating process. The variation in thebarrel rotation speeds according to one mode of this invention isachieved by varying the size of lineshaft or individual drive gearsopposite those stations requiring dierent speeds.

An object of this invention is to provide an automatic continuous bulkplating or treating machine having elevator and transfer or conveyordevices employing simple chain drives, the elevator device employing themechanical advantage of the block and tackle.

An object of this invention is to provide a machine having horizontalbarrels each carried by an individual carriage and an individualpantograph-type arm suspension, which permits the elevator device todeliver a vertical motive force independent of the conveyor mechanismand over a vertical distance which is adjustable according to the needsof the process and work. This result is accomplished by providing alifting member which engages the elevator and lifts each suspensionindependently of its carriage. Variation in height of lift is achievedby varying the length of the lifting member or its connecting mechanism.

Still another object is to provide a machine having an elevatormechanism incorporating means for supporting the barrels at all timesduring their up-and-down movements and which will selectively disengagethe barrels in those stations where the vertical movement is notdesired. The apparatus provided for this purpose includes an elevatorrail suspended around the machine opposite those stations where supportor lifting of the barrels is required, a delayed set-down, skip-stationor early-lift device at some stations, and engaging and disengagingfingers on the ends of the elevator rail at those stations wherevertical movement is not required.

Yet another object is to provide a machine having a barrel elevatingmechanism incorporating a device for either an early lift-up, delayedset-down or skip-station function, which device or devices areintegrated with the main elevator and conveyor mechanisms of the machineto permit continuous, simultaneous advance of work. The apparatusprovided for this purpose includes a worksupporting elevator bracketwhich is operated independently of and above the main elevator rail.

Another object is to provide a machine having a selfadjusting couplingdevice between a single conveyor chain and a plurality of barrelcarriages to compensate for chain stretch and wear and commercialtolerances of machine frame elements.

An object is to provide a machine having a line-shaft type of barrelrotation drive and means including a combination of taper-faced cams andspur drive gears forming an epicyclic gear train for facilitatingengagement of individual barrel rotate power take-off devices on eachbarrel carriage.

An object of this invention is to provide a machine of the return typeemploying a combination of line shaft and individual barrel rotationdrives on the curved ends of the machine.

Another object is to provide a machine having on the individual barrelcarriages a barrel rotating power transmission system of constant beltor chain length in both vupper and down positions of the barrel.

Still other objects, features, and advantages of the present inventionwill become apparent in the following detailed description taken inconjunction with the accompanying drawings, in which:

Figure 1 is a plan view of the plating machine of'this invention withmuch of the detailed mechanism removed v in order to show the generaldisposition of the frame, tanks, barrels, tracks, elevator, etc.;

Fig. 2 is an elevational view, with portions broken away, of thesupporting framework showing the disposition of some of the power drivemechanisms which operate the various machine parts;

Fig. 3 is a cross sectional view of the complete machine shown in Figs.l and 2, showing the details of the barrel carriage, the barrelsuspension, the elevating means, the delayed set-down means and thebarrel rotating means, the section being taken along the line 3-3 ofFig. l;

Fig. 4 is an enlarged top view of a portion of the conveyor chainsuspension, the portion enlarged being indicated between the arrows 4-4of Fig. 2;

Fig. 5 is an enlarged side view of the compound line shaft connections,the portion enlarged being indicated by the circle 5 in Fig. 2;

Fig. 6 is a side elevation of one station of the machine of Fig. 1showing further details of the barrel carriage, the barrel suspension,barrel rotation drive mechanism, and the barrel elevator mechanism, theview being taken in the direction of the arrow 6 in Fig. 3;

Fig. 7 is a sectional view showing the details of the individual powertake-olf means located on each of the barrel carriages, the sectionbeing taken along the line 7-7 of Fig. 3;

Fig. 8 is an end-view, partially in section, showing some of the detailsof the conveyor chain drive mechanism, the section being taken along theline 8-*8 of Fig. 2;

Fig. 9 is an end view, partially in section, showing the details of thedelayed set-down mechanism, the section being taken along the line 9-9of Fig. 2;

Fig. 10 is a sectional view through the upper set-down sprocket, thesection being taken along the line itl-l0 in Fig. 9;

Fig. 11 is an enlarged plan view, with portions broken away, showing thedetails of the right-hand end of the machine of Fig. 1 and in particularthe mounting of the individual barrel rotation motor and drivemechanism;

Fig. 12 is a side view showing further details of the barrel-rotatingmotor and drive mechanism of Fig. ll,

. and their mounting, the figure being viewed in the direction of arrows12-12 of Fig. 11;

Fig. 13 is an end view of the barrel rotating mechanism, the view beingtaken in the direction of the arrows 13-13 of Fig. 11; and

Fig. 14 is a circuit diagram of the complete controls system for themachine of Figs. l to 13.

Referring now to the drawings and particularly to Figs. 1 to 3, it willbe seen that the machine illustrated has a central frame of structuralsteel members surrounded by a plurality of tanks arranged end-to-end toform a continuous elliptical pathway thereabout. As will be seen in Fig.1, the machine is designed for ilow of work in the direction of thearrows. Thus, when Fig. 1 is laid on its side, the upper right-handcorner of the elliptical tank system will be the load and unloadingstations. At the left-hand end of the machine, a single, continuous,curved tank is provided for a iinal plating operation. In the upper legof the machine between the latter curved portion and the loading stationlocated on the upper righthand end, there are situated a number ofneutralizing, cleaning, pickling and other pre-plating work preparationstations, a few of which are indicated in Fig. l. Following the curvedplating station, the lower horizontal leg of the elliptical tankcontains the drag out, water rinse, bright dip and nal rinsingoperations.

Although the tank and the entire machine of Fig. 1 is shown broken inseveral places to reduce it to a convenient size for drafting purposes,it will be understood Athat the machine is designed with a suiicientnumber of 1 "1 l l x l 1 L I Plate 1 1 lCyanide l `1p 1 l l j l l l 11mi-r 1 1o.w.R l 1 l l 1 l l 1 p -Lm g 1 1 l l f l trickle l 1 l l 1 l 1l T f V Il i I ,Pickle l 1 l 1 1 Ln n 1 1 l 1 l i lDragout 1 C.W.R I I l1 1 i 1 i n 1` l l i 1C.W. R. l Clean 1 1 1 1 1 1 1 ..l

T i 1 l l l Bright dip 1 i 01am l l l 1 l 1 l t T 1 *rrr* 1 1 l l l I 1ow. R. l INeutmnze 1 l 1 1 l 1 .l

\ T-hl I l 1 lLoad l 1 T /1 1 lrr-"W l n.w.R l 1 .l

`-l l 1 :Upload This cyanide zinc plating process is vseen to requirefourteen separate stations exclusive of load and unloading. In suchaprocess the neutralizing, cleaning, pickling, cyanide dip and cold (C.W. R.) and hot water (H. W. R.) rinse steps are in no wise critical.That is, the time of immersion in these `stations can vary somewhat.Thus, the curved plating station on the left-hand end of the machine asseen in Fig. 1 is designed to have a length which is a simple multipleof a single station for carrying out any of the preparatory and clean-upoperations. The solution used in the bright dip station, however, is anacid solution of considerable strength. The work is immersed in lthissolution for only a matter of a few seconds in order to generate asmooth, shiny surface. lf the work is allowed to remain Vinthis solutiontoo long, the plated coating would be damaged or 'entirely removed. Forthis station, therefore, a delayed set-down 6 mechanism is provided inkorder to obtain a very short period of immersion.

The machine illustrated in Figs. l to 13 is of the return type wherein aseries of horizontal plating barrels containing the small bulkworkpieces are successively immersed in cleaning solutions, picklingsolutions, and a cyanide dip solution preparatory for plating. Themachine incorporates an elevator mechanism including a lifting rail orbeam for simultaneously raising and lowering a number of the barrels, atransfer or conveyor mechanism for simultaneously advancing all barrelsfrom one station to the next while elevated, a means for rotating thebarrels in Athose stations Vrequiring barrel rotation, and a delayedset-down mechanism for obtaining shorter immersion times and/or longerdrainage times at those stations where necessary. In the machineillustrated, the barrels are lifted and lowered on the straight-sidedportions and right-hand end of the machine, the barrels remaining in thelower lor submerged positions at the leftend lof the machine during theplating operation.

The machine of Figs. 1 to 13 incorporates `a number of separate powersupply means, all electrical in nature, and it employs chain and V-beltpower transmission systems` For example, separate -barrel rotating lineshafts are provided to rotate the barrels on the straight-sided portionsof the machine and individual barrel rotation drives are provided oneach curved end. The transfer or conveyor system is powered lby acontinuous chain and is supplied by one power source. The elevatormechanism and delayed set down mechanism are `driven from separateelectrical motors, as will be more fully described hereinafter.

Referring now vto Figs. 1 'and 3 of the drawings, it will be seen thatthe frame of the machine is formed of two spaced-apart bottom channeliron members 20, 20 running the length of each of the straight sides, aplurality of horizontal bottom I-beam members 21, 21 connecting the sidechannels 20, and a number of central, vertical columns 22, 22 eachcomposed of a pair of juxtaposed channel irons to form a box-shapedcolumn. Attached to either side of the top ends of the vertical columns22, 22 (see Fig. 3) is a pair of upper longitudinal channel iron members23, 23 each of which extends the length of the straight sides. Securedacross the upper ends of columns 22, 22 and longitudinal top channels23, 23 are a plurality of horizontal inverted T-iron top cross members24, 24. At the ends, the frame is braced by inclined T-iron braces 25,25. A series of shorter vertical angle iron uprights 26, 26 (see Fig. 3)-are located inside the base channels 20, 20 and are secured at the topby horizontally welded angles 27, 27 .to form a series of platformmembers along the straight length of the machine. The latter platformmembers are braced transversely by diagonal braces v28, 28 (only one ofwhich is shown in Fig. 3). The rectangular platform members serve tosupport various of the drive mechanisms and the conveyor mechanism, aswill be described hereinafter. Slidably attached to a number of thevertical central co1- umns 22, 22 at a convenient height above the oorare a number of inverted T-iron or channel iron horizontal members 29,29 which support an integral elevator rail or beam 30, which extends oneach side of the machine and is curved to pass around vthe right-handend. The members 29, 29 and the elevator beam 30 form an elevatorchassis. About the central frame thus defined is located a series oftanks. The tanks (Fig. 3) are supported above the floor ontransversal-beams 31, V31 `by an outer support 32 and an inner channeliron support 33 secured atop bottom base channels 20, 20 in `order tokeep the tank bottoms dry and free of corrosion.

Barrel carriage assembly A plurality of horizontal vplating barrels .arecarried on l. 7 clearly in Figs. 3 and 6 of the drawings. The barrelcarriages run on the channel-shaped elevator rail or beam 30 which restson the horizontal rail supports 29, 29 when the beam 30 is elevatedduring transfer. Each individual barrel carriage (Fig. 3) comprises arectangular, vertical frame having two vertical side members 40 andthree horizontal cross members 41 (Fig. 6). Carried in roller slides 58,60 located in the middle of top and bottom cross members 41 is a singlevertical I-beam leg 42. Vertical leg 42 slides up and down in slides 58,60 as the elevator rail 30 is raised and lowered, thus actuating thelift mechanism, as will be more fully explained hereinafter. The leg 42carries on its lower end a small wheel 43 which runs along the top ofthe elevator rail 30 during horizontal transfer operations. Each of thecarriage side members 40 have on their top ends an inwardly-extended armor bracket 44 which carries a horizontal guide wheel 45. The wheels 45roll in an upper track defined by inner angle iron 47 and outer channel48 which are secured in spaced-apart relationship to the lower surfaceof the outer ends of top cross members 24, 24. The upper track extendsentirely around the machine. To insure against transverse movement ofthe carriage, the lower extremities of side members 40, 40 are providedwith arms 49 which are secured thereto and extend inwardly and carry ontheir inner end extremities guide wheels 50. The wheels run in a lowertrack defined by an inner angle iron 52 and an outer channel iron 53secured to platform members 27, 27. The inner side 52 and outer side 53of the track are secured together by bolts and spacers indicatedgenerally in Fig.

3 by the numeral 54. The lower track thus defined likewise extendsentirely around the machine.

When the elevator beam 30 is in its down position, the main verticalcomponent of the Weight of the barrel and its carriage assembly is takenup by the arm 49 on an Oilite thrust pad 55 which rests on a steel pad56 secured to the top edge of channel 53. An adjustable gib arrangement57 secured to arm 49 extends under pad 56 to prevent the verticalmovement of the elevator rail 30 and leg 42 from separating the pads 55,56. The Oilite pad 55 can be tapered inwardly and outwardly from itsmiddle to partially compensate for slant or inaccuracies in the top edgeof channel 53 which supports the pad 56. The pad 55 then will rest oneither taper and prevent binding of the carriage in its guide tracks.

The lower carriage cross member 41 carries on the middle of its outerside a roller guide 58 which serves to guide leg 42 as the carriage israised and lowered. A similar roller guide 60 is provided in the centerof the upper horizontal carriage member 41 for guiding the upper end ofleg 42. The members 4), 40; 41, 41; and 42 with their accessory partscomprise a vertical carriage frame on which are mounted and carried anoutwardly extending pantograph barrel suspension.

Barrel suspension Near the upper ends of the carriage side members 40.there is rigidly attached to vertical members 40, 40 a l rectangularframe composed of a pair of lower horizontal members 70, 70, a pair ofupper horizontal members 71, 71 (only one of each being visible in Fig.3), and a pair of longitudinal angle iron cross bars 72, 72. The framemembers thus provided form a rigid platform on which is mounted anindividual power take-ofi assembly for v' a V-belt driven barrelrotation mechanism', as will be explained more fully below. Pivotallyattached to each 80. The latter is connected to cross bar 76 by avertical, pivotable Y-shaped linkage 81. The arms 75, and 78, 78together with cross bars 76, 77 and 79 and llnkage 81 form a set ofpantograph arms which are lifted up and down by vertical up-and-downmovement of liftdip leg 42. The lift bracket 8i) and/or the Y-linkage 81can be made adjustable to permit shorter or higher lifts with a givenlift leg 42. The latter also could be made adjustable as to length, ifdesired. The distance of upward travel of the elevator rail 30, however,actually is determined by electrical limit switches governing theelevator as will be explained more fully hereinafter. The distance ofdownward travel of the arms 75, 78 is limited by the location of a stopplate 74 attached to the top end of leg 42, the plate 74 coming to reston the top rollers of upper roller guide 60 when the leg is in its lowerposition and the elevator beam 30 has been lowered to its bottom restposition some distance below Wheel 43. The plate 74 also can ybe madeadjustable, 1f desired, to vary the depth of immersion.

At the ends of pantograph arms 75, 75 and 78, 78 on the projecting endsof horizontal cross bars 77 and 79, there is suspended a pair ofvertical barrel hanger arms 82, S2. The ends of the pantograph arms 75,75 and 78, 78 are litted with U-shaped saddles 83, 83. In the saddles83, 83 carried by the arms 75, 75 the cross bar 77 is fitted, and intothose carried by the lower arms 78, 78 the cross bar 79 is tted. Thehexagonal plating barrel 84 is suspended in bearings located in thevertical barrel hanger arms 82, 82. The barrel 84, therefore, will belifted vertically in a slight inward-upward arc by the suspensionassembly formed by arms 75, 75 and 78, 78 and cross bars 76, 77 and 79.

It is easily seen that instead of the horizontal type of barrelillustrated, each of the vertical barrel hanger arms 82, 82 could `bereplaced by arms, hooks or hangers for supporting non-rotating baskets,plating racks and the like. The use of horizontal rotatable plating orcoating barrels is much preferred, however.

For plating or electro-cleaning, there is attached to the upper ends ofeach of the carriage uprights 40, 40 a spring-loaded, pivotableelectrical contact shoe 85, which makes -contact with an insulated busbar 87 suspended from the upper horizontal frame members 24, 24 onbrackets 86, 86. Cathode cables 88, 88 secured to each of the upperpantograph suspension arms 75, 75 serve to connect the contact shoes 85,with shorter, expendable lower cables 89, 89. The latter connect withcathodes (not shown) located inside the lbarrel S4. Ball-type anodecontainers 240, 240 are suspended in the tank on each side of the barrelas shown in Figs. 3.

The electrical circuit thus described furnishes current for any platingor electrocleaning stations. The tank shown at the left in Fig. 3 is notelectrified.

Barrel rotating mechanism The lineshaft drive mechanism will bedescribed before the individual power take-off units. There is alineshaft on each long, straight side of the machine. one of the latterbeing indicated generally in Fig. 2 by the numeral 90. The lineshafts90, 90 are suspended on arms which depend from the upper centralhorizontal T-iron cross members 24 secured across the top oflongitudinal channels 23. A bracket 91 is mounted on the side of each ofchannels 23 between upper horizontal cross beams 24. On each of thesebrackets are mounted a direct-coupled electric motor and reduction gear92. The lineshafts 90, 90 are driven by a triple roller chain drive,indicated collectively by the numeral 93. The lineshafts 90, 90 (one oneach straight side of the machine) are supported in bearings 94 securedto a plurality of the downward hanging arms 95. At intervals oppositeeach station along the machine, the lineshafts 90, 90 are provided withpower take-off spur gears 96 each having an attached tapered cam 97 inthe direction facing the Iapproaching barrel carriages in order tofacilitate engagement with individual barrel rotation take-olf gears.This arrangement is very similar to a shrouded gear. The leading andtrailing edges of the teeth of gears 96 are chamfered to facilitatemeshing.

The lineshaft 90 shown in Fig. 2 is compounded on is right-hand end toreduce the rate of rotation in the last washing and post-treatmentstations. Fig. shows an enlarged view of the circled area of Fig. 2wherein the lineshaft 90 is shown to carry a small end gear 98 whichmeshes with a larger gear 99 carried by the compounding shaft 100. Onthe opposite end of the compounding shaft 100 a small gear 101 mesheswith a larger gear 102 on the lineshaft stub end or continuation 103`with the net result that the rate of rotation of the stubshaft end 103is such that the end barrels will rotate something like 1-2 R. P. M'.as' against 6 R. P. M. for those connected to main section of lineshaft90. This compounding arrangement can be varied to deliver any desiredrate of barrel rotation at any station. It also `may be `designed toprovide slower rates of rotation than is possible to `obtain withindividual geared motor drives.

The individual barrels are driven off lineshafts 90, 90 by theirindividual power take-off mechanisms meshing with lineshaft gears 9 6.The individual power take-oft `mechanisms are more clearly illustratedin Figs. 3 and 7, particularly the latter. As indicated above, theindividual power take-olf units are mounted, one on each carriage, onthe platform formed by the lower horizontal members 70, 70 and a pair oflongitudinal angles 72, 72. A small spring-loaded gear 111 is carried ina pair of arms 112, 112, the latter being integral with a second pair ofarms 113 set at an angle thereto, the arms 112, 113 forming a rockingassembly which is pivoted on shaft 114 and supported by spring 115 andbracket 116. The shaft 114 is journalled in two upstanding ends of ashaft support housing 117. Also attached to the shaft 114 is a second,xed gear 118 which meshes at all times with the spring-loaded gear 111.Thus, the small gear 111 rs't makes contact with the tapered face 97 `oflineshaft gear 96 and is biased outwardly a short distance and at anangle until its teeth fall into smooth full-face engagement with theteeth of the former. The gears 96, 111 and 118 form an epicyclic geartrain. Damage to the teeth of Iboth gears is prevented by thisarrangement since the gear 111 remains in engagement with gear 118,

and, as will be seen in Fig. 7, the cam 97 and the hub 111tz of gear 111are in contact to prevent binding by too deep engagement of their teeth.The shaft 114 thus is driven, the rotation being transmitted to a V-beltpulley 119 on the end thereof. A V-belt 120 runs over sheave 119 down toa drive sheave 121 located on the vertical barrel hanger arm 82 andreturns over the top `of an adjustable idler pulley 122 located in thelower pantograph arm 78. The arms 75, 75 and 78, 78, together withsheaves 119, 121 define a belt transmission system which has a constantlength during upward and downward movement of the barrels.

Referring now to Fig. 6, the V-belt drive pulley 121 is attached to ashort pinion shaft 123 located in barrel hanger 82. On the inner end ofshaft 123 is a pinion gear 124 which meshes with a second inner gear 125carried by a second short shaft 126 located in arm 82, the shaft 126 inturn carrying another gear 127. Gear 127 in turn meshes with a gear 128carried on a shaft 129 below shaft 125. Gear 128 meshes with a largering gear 130 attached to the hub 131 of the Ibarrel 84. Thus, theV-belt 120 actuates the vertical gear train carried on the hanger 82.The lineshafts serve to rotate the barrels only on the twostraight-sided lengths of the machine, however. On each of the curvedends of the machine separate drive motors and gearings are provided inthe machine illustrated, although gearing connected to the lineshaftscould be substituted therefor. It is also to be understood that insteadof the lineshafts and end drives, an individual gear head motor could bemounted on each carriage with a trolley-type power take off.

Only the individual barrel rotating drive for the right end of themachine is shown in detail in Figs. 11-13 of the drawings. Itis to beunderstood that a similar means is provided at the opposite left-handend, as is indicated in Fig. l. In Fig. l1, the projecting ends of theupper longitudinal top channel beams 23, 23 serve as a support for abase plate to which are attached a downwardly-depending gusset plate 141and a box-shaped member 142. On one side of plate 141 is mounted anelectric motor 144 having tension-adjusting means 14411 incorporated inits base. On the other side of plate 141 is mounted a side-mountingreduction gear 145. The motor 144 drives the reduction gear 145 by meansof a V-beit drive indicated generally by the numeral 146. A large spurgear 147 is mounted in bearings 148, 148 which are tted into thebox-shaped supporting member 142 (as shown in Fig. l2). The reductiongear 145 carries a pinion gear 149 which meshes with the large drivegear 147. Like the lineshaft gears 96, 96, gear 147 has a beveled cam147@ attached to its face and facing the direction of approach of thebarrel carriages. The flexible individual power take-01T gears 111, 111on the barrel carriages make contact with the tapered cam 147a and flexsuiciently to make an angular full-face sliding engagement with gear147. The leading edges of `gears 111 and 147 are chamfered to facilitatethis type `of engagement.

In the machine illustrated the drive mechanism of Figs. ll-l3 rotatesthe barrels at about l R. P. M. The individual drive located in theleft-hand rounded end of the machine is similar in details and mountingbut for the exemplary cyanide zinc plating process utilizes a reductiongear adapted to rotate the barrels at 6 R. P. M., the same speed as isderived from the lineshafts 90, 90.

Conveyor transfer mechanismk There have been described thus far thedetails of the barrel carriage, barrel pantograph suspension, and barrelrotating drive mechanisms. The carriages are moved around the machine bymeans of a chain drive conveyor mechanism indicated generally in Figs. land 2 and shown in greater detail in Fig. 8. As will appear most clearlyin Fig. 2, a motor 150 is mounted at one side of the machine adjacentthe floor and in the left-hand end of the machine on a support 151 ofchannel iron secured atop bottom horizontal frame members 21, 21. Asmall platform located directly above and slightly toward the center ofthe machine with respect to the motor 150 is composed of four short,vertical angle iron columns 152, 152. Atop the latter platform ismounted a speed reducing unit 153. On an adjacent platform formed of apair of longitudinal I-beams 154, 154 secured atop members 27, 27, and a`pair of horizontal top channel iron members 155, 155, there is secureda pair of sprocket-supporting hubs 156, 156. The motor 150 drives thespeed reducer 153 b-y means of a triple V-belt drive composed ofa sheave157 on the motor, three V-belts 158, 158 and a. large sheave. or pulley159 located on the speed reducer 153, the sheave 15.9 incorporating atorque-limiting clutch, not shown. The speed reducer type, having ahorizontal sprocket 160 mounted in its top. In, the hubs; 156, 156 thereare, mounted a pair of identical chain sprockets 161, 161. The speedreducer 153 drives sprockets 161, 161 by means of a single width,roller-type chain 162. The chain 162 travels over an idler sprocket1.63` carried in a hub 164 which is mounted on channels 155,155.

Alsomounted on each of hubs 156, 156 there is a conveyor drive sprocket165 for engaging a main conveyor chain 166 on each side of the machine.The individual carriages are adjustably secured toy the conveyor chain166 by means of two bolts 168, 168 which replace chain pins, the bolts168 being attached to a block 167. The

153 is of the top take-olf i block 167 is fitted into a slot in arms169, 169 so as to slide in and out to provide clearance for pivoting ofthe connection in the curved ends of the machine. This arrangement alsopermits self-adjustment in order to prevent binding due to frameinaccuracies and the like. Each of the arms 169, 169 is rigidly attached(see Fig. 3) to a Vertical barrel carriage member 40. The chain 166 (seeFig. 8), runs in a protective trough 166a which is attached to thehorizontal I-beams 155, 155.

The conveyor chain 166 thus extends entirely around the machine andsimultaneously moves all individual barrel carriages a given distancewhich distance is referred to as the stroke of the machine. The strokeof the machine is determined by the distance between the centers of theindividual tanks. In the machine illustrated, a typical stroke would beabout four feet.

As will be seen in Fig. l, the curved ends of the machine are providedwith a plurality of idler sprockets 170, 170, each of which are attachedto individual arms 171, 171, the latter in turn being attached tocurved, horseshoe-shaped members 172, 172. The horseshoe members 172,172 in turn are attached to vertical columns 22, 22. The sprockets 170guide and support the chain 166 in the curved end sections of themachine.

Elevator mechanism In order to transfer the barrels from one station toanother, they must be lifted to clear the edges of the tanks. In themachine illustrated, this is performed by raising the elevator chassiswhich is composed of rail 30, horizontal arms 29, 29 and vertical liftlegs 185, 185. As will be noted from an inspection of Fig. 1, theelevator rail or beam 30 is not continuous, that is, it does not extendentirely around the machine. At the left-hand end of the machine in Fig.l, the barrels are not elevated and they remain immersed in the curvedplating tank.

At the right-hand end of the machine, in the final hot water rinse,unload and load stations, the barrels are raised and loweredsimultaneously with the barrels of the straight-sided portions of themachine. The elevator rail 30, therefore, begins just inside the end ofthe continuous curved left-hand plating tank 180, as seen in the planview of Fig. 1, and continues along the length of the lower leg of themachine around the curve of the right-hand end of the machine and thefull length of the straight upper leg of the machine to a point oftermination just inside the upper end of the tank 180. Both ends ofelevator rail 30 are provided with hinged, spring-loaded orcounterweighted pick-up or drop-off lingers, respectively, 181 and 183,in order to disengage or engage the first and last barrels. In the upperleg of the machine, as will appear in Fig. 6, the end of the elevatorrail 30 is provided with a normally-erect spring-loaded orcounterweighted dropofi finger 183 (see Fig. 6) which is depressed bythe wheel 43 carried by each of the vertical lift-dip legs 42, 42. Wheneach carriage has travelled out to the end of linger 183, the drop-ofifinger 183 is disengaged when the elevator rail continues its downwardmovement below the lowest position of the barrel. In this position, thespring or counterweight causes the finger 183 to pivot to the verticalposition in which position it will clear the carriage wheel 43 in thenext succeeding upward movement of the elevator rail 30.

The pick-up linger 181 attached to the end of the elevator rail 30 inthe lower leg of the machine is normally extended so as to engage in itsupward travel the carriage then located at that station. When the rail30 is lowered, however, another barrel has moved into position and thefinger 181 will be flexed upwardly by contact with the leg 42 or thewheel 43 and then dropped back into extended position when the rail 30has continued below the pick-up position. The fingers 181, 183 preventdamage to the barrel carriage and provide a means for smoothly engagingand disengaging with carriages located in the two stations.

The elevator rails 30, 30 are lifted vertically by the T-shaped liftingmechanism formed by horizontal rail support members 29, 29 and verticallift pieces 185, 185 which are slidably supported by the verticalcolumns 22, 22. The lift pieces 185, (see Fig. 3) have brackets 186, 186located top and bottom, the latter having outer guide rollers 187, 187on either side thereof to smoothly guide the up-and-down movement.

The elevator mechanism is powered by a motor 188 mounted on an extensionof the conveyor drive platform. The motor 183 drives a speed reducer 189by means of a V-belt drive sheave 190, the latter incorporating atorquevlimiting clutch (not shown). The speed reducer 189 has a pair oftake-off sprockets 191, 191, one on each side. Along the top of thelongitudinal top frame members 23, 23, there are secured a plurality ofbrackets 197 (Fig. 4) which support a series of short shafts 196.Attached to the shafts 196 are a number of outer sprockets 193 and innersprockets 194. The sprockets 191 engage a pair of elevator chains 192,192:1 which extend vertically and pass over the outer sprockets 193,193a shown in Fig. 4. The chains 192, 19201 pass over the second set ofouter sprockets 193b, 193e and then down to a counterweight 192bslidably supported in column 22. The other ends of conveyor chains 192,192a are wrapped around reducer sprockets 191, 191 and brought upwardlyto be attached to either end of a chain block 198. The distance oftravel of block 198 is indicated in dotted line. From the top of block198, two pairs of chains 201, 202 are secured and extend vertically topass over the inner sprockets. Chains 201, 201 pass over inner sprockets194, 194a and then are brought along the top to the left-hand end of themachine, one passing over the top of inner sprocket 1Mb and down undersprocket 195 attached to lift piece 185 and secured at its end tochannel 23 at 203. The other of chains 201 is continued down the lengthof the machine so as to pass over sprocket 194C, then down under anotherlift piece sprocket 19S and its end finally secured to channel 23 at204. The other pair of chains 202, 202 are brought upward over sprockets19461', 194e and then passed lengthwise to the right-hand end of themachine. One of the latter chains 202 is passed over sprockets 194:1 and1941, then down under still another lift piece sprocket 195 and attachedto channel 23 at 205. The second of chains 202 is brought up oversprocket 194e and extended the length of the right-hand end of themachine to pass over sprocket 194g, then down under lift piece sprocket195 and its end secured to the channel 23 at 206. Thus, when reducer 189is energized in the direction of the solid arrow, a downward pull isexerted ron chains 192, 192, block 198 and chains 201, 201 and 202, 202so as to exert an upward pull on all vertical lift pieces 185, 185, thecounterweight 192b meanwhile travelling downwardly. When the reducer 189is energized in the direction of the dotted arrow, the vertical liftpieces 185, 185 will be lowered and the counterweight 192b will beraised. The main function of the counter'- weight 19222 is to maintain atension on the chains 192, 192 to keep them wrapped around speed reducersprockets 191, 191.

The lifting mechanism just described raises the elevator rail 30 and allbarrel carriages in Contact therewith. At those stations such as thebright dip station where shorter immersion times are required, asecondary elcvating means is pro-vided for advance-lift, delayed setdownor skip-station function.

Delayed set-down mechanism This secondary elevating mechanism is shownat the bright dip station in the right end of the machine, generaldetails being shown in Fig. 2 and in more detail in Fig. 9. As shown,the mechanism is used as a delayed set-down mechanism. lt is to beunderstood that it can be used as an early lift or skip mechanism, ifdesired. At this station, two vertical channel iron members 210, 21)simamener 13 ilar to columns 22, 22 (see Fig; 10) are provided asvertical guides. Two pairs of outside vertical arms or brackets 211, 211are attachr d top and bottom to a ilat shoe or plate 212 riding on theflanged edges of channels 210, 210. The arms 211, 211 each carry twopairs of large, tapered rollers 213, 213 (see Fig. i), one pair at topand a pair at the bottom. The rollers 21-3, 213 iit inside theoutstanding channel edges and guide the mechanism in its Verticalmovement up and down. An integral projection 214 of the plate or shoe212 rides on the top of the elevator rail 30. This projection or bracket214 has tapered edges (not shown) to facilitate the climb ofwheel 43 toa position atop it. Attached to the vertical members 210, 210 are threepairs of arms. The upper of these pairs of arms 215, 215 bear a shaft216 on which is secured a chain sprocket 217. A middle pair of arms`2-18, 218bear a shaft 219 on* which is attached an idler chain sprocket220. The lower arms 221, 221 carry a shaft 222 on which is securedsprocket 223. A motor 224 is directly connected to a speed reducer 225.The speed reducer 225 drives a sprocket 226. A chain 227 passes oversprocket 226, idler sprocket 220, thence over lower sprocket 223 and upbetween the uprights 210, 210l to pass lover t'opsprocket 217.

Attached to the face of plate 212 is a pair of brackets 228, 228 inwhich is supported a rod 229. At the middle of rod 219 there is attacheda `dog 230. The dog 230 is spring loaded through a pair of arms 231.,231 and tension springs 232, 232 so as to maintain continuons contactwith chain 227. When the elevator beam is raised by the above-describedelevator mechanism the plate 21.2 carried by bracket 214 is also raisedvertically until it reaches the position shown in dotted line at top ofFig. 9. When this is done, the dog 230 `slides over the kchain links dueto its shape and angular disposition. When the elevator rail 36 islowered, however, the step-shaped 'end of the dog 230 engages the chain227 and prevents the lift leg 42 (which is riding on top of vbracket214) from dropping to -t-he lower position. When the reducer 42215 is`driven in the direction of the solid arrow, however, the chain 227 isslowly lowered to the lower position and the barrel likewise is lowered.When the 'elevator rail 30 is raised again, the delayed set-downmechanism also is raised, the dog 230 sliding `over the chain as before.If the motor 224 is reversed, the same mechanism can be employed as anadvance-lift mechanism. In this latter situation, the speed reducer 225is energized in the direction of the dotted arrow. An advance-liftmechanism can be employed to raise a plating barrel yto the uppertransfer position in 'order to reduce immersion time and to allow`greater time for solution drainage. Ii'f the `motor 224 is -notenergized, the mechanism just described will 'function to cause a barrelto skip the station because the Ibracket 214 will remain in the uppernposition to be picked up by the elevator rail on the next cycle.

Controls The machine of the invention -is provided with limit switchesto control the various elevating, transferring 'and delayed set-downmotions. The various drivemotors Aare controlled by electrical controlsoperating in -conjunction with `the limit switches and electricaltimers. These control elements combine to produce a pre-selectedsequence of operations which advance the barrels from 'one station toanother and maintain them immersed on "a V'pre-selected time basis. Fig.14 shows acomplete wiring diagram of the controls for the machine ofFigs. 1-13. The diagram of Fig. 14 incorporates controls for `the motorof a blower of a Ventilating system which `is `-not shown in any of thedrawings since it fis only an accessory to the plating machine.Nevertheless, its operation is necessarily `integrated with the platingmachine proper.

Since the control circuit of Fig. 14 controls the operation of thevarious mechanisms Adescribed above, the

14 v description of the control circuit will be incorporated with adetailed explanation of the stepwise operation of the integratedmachine. It must be borne in mind that the various limit switches aretoo small to appear in any of the drawings. Their exact location, aswill be understood, may be varied somewhat according to the type ofoperation desired of the machine.

As shown in Fig. 14 power is supplied to the motors and control circuitthrough a set of three-phase power input leads 300, 300 which areattached to a main power switch 304. From the latter, three power leads301, 302 and 303 are taken off to supply the eight motors of the machineand accessory parts. The vmotors are identified both by letters M-lthrough M-8 and by suitable legends indicating their function. All ofthe motors are connected in parallel with all of the barrel rotatemotors being controlled by one relay (CRZ) and each by an overloadswitch.

A transformer 305 is provided for isolating the control circuit andsupplying current at the correct voltage. The two terminals of thetransformer are connected to two leads 306, 307 which are connected totwo hand-operated override stop switches 308, 309, the former located inthe blower control circuit and the latter in the barrel rotate controlcircuit. The latter switches are normally closed when the machine isoperating properly and are intended to be tripped by the operator whenit is desiredv to stop either the blower or the barrel rotate motors.The blower motor circuit is controlled by relay CR1 which has a set ofcontacts CR1-1 in the blower motor circuit. The barrel rotate motorcircuit is controll-ed by relay CR2 having vseveral sets of contacts,GRZ-1 located in the main control circuit and CR2-2 in the barrel rotatemotor circuit ahead of the motors Ml--M4. Blower motor relay `CR1 isenergized by ,pressing start button 310. Barrel rotate relay CR2 isenergized by pressing start button 311. When this is done, theventilator blower is running and the barrels are rotating in allstations except the load and unload stations.

The main control circuit is energized by pressing main motor startswitch button CM connected between leads 306' and 307. As shown, thetransfer conveyor motor M7 is controlled Aby a relay CR3 havingra setlof contacts CRS-1 in the motor circuit, the elevator motor by areversible motor starter relay CR4 having a set `of contacts CR4A in thecircuit of an up coil and a set of contacts CR4B in the circuit of adown coil, and the delayed set down motor by relay CRS which has a setof contacts CR5-1 in the motor circuit.

A `mechanically-held relay LU1 is the 'traffic center of the controlcircuit. This relay is tripped by the dwell timer TR2 and functions toenergize the elevator, transfer and set-down motors. To do this, relayLUI has four sets of contacts, LUI-1 in the circuit of the `transfermotor relay CRS, LUI-2 in the elevator up limit switch (LS1) circuit,LU143 in the circuit of the trans- -fer limit switch LS2, and LUI-4 inthe circuit of the set down limit switch LS3 and elevator down 'limitswitch LS4.

The circuit is `shown in Fig. 14 with the machine and vits parts innormal starting position, that is, with the elevator rail up and the uplimit (LS1) vand transfer limit v(L82) switches operated. .In thisposition, the machine is Iready to transfer. A lloaded barrel `is inthe-load station ready for transfer to the iirst, or neutralizingstation.

The pressing of main motor control button CM energizes the transferstarter relay CRS through up limit switch LS1-1 and contacts LUI-1. Thisvstarts the transfer motor M-7 and the barrel carriages start moving.This movement breaks contact between a cam on `one of :the carriages and'transfer limit switch LS2. This completes the circuit through LS1, LS2and LU1-2 to hold relay CR3 in operation. When .the transfer iscomplete, the cam on another carriage trips transfer limit switch LSZand breaks the CRS circuit. This stops the transfer motor. At the sametime, tripping of LS2 completes the circuit to elevator starter downcoil CR4B through LUI-3, LSZ, and elevator down limit switch LS4. At thesame time, a circuit is opened to dip relay timer TR1 through relayLUI-4, transfer limit switch LS2 and delayed set down limit switch LS3.The elevator motor then is running and the chassis is moving down. Thecarriage in the delayed set-down (bright dip station), however, remainsup. When the chassis has moved down a short distance, it releases theelevator up limit switch LS1. At the bottom of its drop, the chassisoperates the down limit switch LS4 which breaks the circuit to theelevator down coil CR4-B and stops the elevator motor.

Simultaneously, operation of limit switch LS4 cornpletes the circuit todwell timer TR2. ln this position, all barrels except that in the brightdip station are immersed in the solutions and are rotating therein.After a selected interval, the set down relay timer TR1 times out andcompletes the circuit to set down motor starter relay CRS. The set downmechanism then starts to move down. At its lowest position, it trips setdown limit switch LS3 which resets set down timer TR1 and drops set downmotor starter relay CRS. In this position, all barrels except those atthe load and unload stations are rotating immersed in the treatingsolutions.

After an interval of such operations, the dwell timer TR2 times out andcompletes the circuit to the up coil of the elevator motor starter CR4Aand trips mechanically held relay LU1. Both the chassis and the delayedset-down section begin to move up. This releases elevator down limitswitch LS4 and the delayed set down limit switch L53 and allows dwelltimer TR2 to reset. The elevator motor `starter up coil CIR4A is held inby a circuit established through LS1 and contacts LUI-3. When thechassis reaches its upper position, the up limit switch LS1 is trippeddropping CR4A and picking up transfer motor starter relay CRS throughLUI-1. This starts the transfer motor M- and the second cycle of themachine begins. The machine will continue to move through consecutivecycles of the type described.

The circuit shown in Fig. 3 incorporates a number of safety limitswitches. Should either up limit switch LS1 or down limit switch LS4fail to operate, the elevator would continue to operate until either upsafety limit switch LSS or down safety limit switch LS7 would be trippedstopping the elevator motor and lighting the indicating light. Shouldtransfer limit switch LSZ either fail to operate or fail to release, theconveyor would continue to operate until transfer safety limit switchLS6 was tripped, the machine stopped and the indicating light turned on.Should up limit switch LS1 fail to release,

the machine will continue to operate until the carriages Y are all downand the dwell time is completed, the machine then stopping until LS1releases. Should down limit switch LS4 fail to release the machine willcontinue to operate until the transfer is complete at which time it willstop until LS4 is released. Thus provided, the machine cannot operate insuch a manner as to suffer damage. The indicating light will promptlynotify the operator and enable him to locate the trouble.

The machine of this invention can be employed to clean, pickle, prepareand plate or coat articles in bulk. In addition to the zinc platingprocess illustrated, the machine may be employed to apply copper,nickel, cadmium and many other metal platings, or phosphate, oxalate andother chemical coatings. The machine utilizes the eflicient highcapacity horizontal type of plating drum which permits high continuousoutput, eticient operation, and the obtaining of high quality platedcoatings. The machine is easily serviced and maintained because theguide rails, sliding mechanisms, conveyor and elevator chains,linesha'fts, and other drive mechanisms are 15 centrally located.Ordinary grease and oil may be employed since drippings will not fall inthe tank. Corrosion of gears, sprockets and chains is eectivelyinhibited by such lubricants. The barrel rotate devices are V- beltswhich require little or no lubrication and are resistant to plating andacid fumes. The machine eliminates many duplicate accessories and isless expensive to build and maintain for a given output capacity thanequivalent batch style capacity.

While it will be apparent that the preferred embodiment of the inventionherein disclosed is well calculated to fulfill the objects above stated,it will be appreciated that the invention is susceptible tomodification, variation and change without departing from the properscope or fair meaning of the subjoined claims.

What is claimed is:

l. Apparatus for plating and chemical treatment of metal articles,comprising a plurality of individual carriage `frames mounted forhorizontal travel, an upper and a lower pantograph arm pivotallyattached to each said carriage frame and extending outwardly therefrom,a work-supporting arm suspended between the said arms, the said carriageframe forming with said pantograph arms and work-supporting arms apivotable parallelogram suspension capable of being raised and loweredabout the points of attachment on said carriage frame, and meanspivotally attached to said suspension at a point outwardly from saidcarriage frames for raising and lowering said suspension.

2. A machine as described in claim l and further characterized in thatsaid raising and lowering means comprises an elevator beam in contactwith a vertical lift leg carried on each said carriage frame, saidvertical lift leg being pivotally attached to said suspension at a pointoutwardly from said carriage frames.

3. An automatic machine for plating and chemical treatment, whichmachine comprises an elongated, centrally-located frame, a guide trackextending around the outer periphery of said central frame, a pluralityof individual carriage frames mounted for movement around said centralframe in said guide track, an upper and a lower pantograph arm pivotallyattached to each said carriage frame, a work-hanger arm suspended fromthe outer ends of said pantograph arms, means pivotally attached to oneof said pantograph arms outwardly from said carriage frame for raisingand lowering said pantograph arms and the said work-hanger arms andmeans for moving said carriages around said central frame.

4. A machine as claimed in claim 3 and further characterized in thatsaid raising and lowering means comprises a vertical lift leg slidablycarried by each said carriage frame and pivotally attached to one ofsaid pantograph arms at a point spaced outwardly from said carriageframe, and an elevator beam which engages said lift legs so as to lifttheir said attached pantograph arms and work-hanger arms.

5. An automatic machine for plating and chemical treatment of metalarticles in bulk, which machine comprises an elongated,centrally-located frame, guide tracks extending around said centralframe, a plurality of individual vertical carriage frames mounted insaid tracks for travel around said machine, an upper and a lowerpantograph arm pivotally attached to each said carriage frame andextending outwardly therefrom, vertical barrel hanger arms suspendedfrom the outer ends of said pantograph arms, a horizontal barrelsuspended between said barrel hanger arms, means for moving saidcarriages around said guide tracks, and means pivotally attached to oneof said pantograph arms outwardly from said carriage frames for liftingand lowering said pantograph arms.

6. A machine as claimed in claim 5 and `further characterized in thatsaid lifting and lowering means comprises an elevator beam mounted onboth sides of said central frame below said pantograph arms, a liftingmember extending from said elevator beam to each pair of said pantographarms and pivotally attached thereto at a point spaced outwardly fromsaid carriage frame, and an elevator including a plurality of centralinverted T-shaped members which engage said beam on both sides of saidframe and a means for lifting and lowering said T- shaped members.

7. In an automatic machine for plating and chemical treatment of metalarticles, which machine has a central frame adapted to be surrounded bya plurality of separate r treating stations, the improvement whichcomprises a plurality of vertical carriage frames mounted for travelaround said machine, a pantograph suspension pivotally attached to eachsaid carriage, a vertical lift leg slidably carried by each saidcarriage frame and pivotally attached to said pantograph suspension at apoint outwardly from said carriage frames, primary elevator means forsimultaneously engaging and lifting said lift legs, transfer means formoving said carriages around said machine while in the elevatedposition, and a secondary elevator means at those stations requiringshorter immersion and longer drainage times for engaging one of saidlift legs while said last-named means is advancing said carriages, forsupporting said lift leg and its pantograph suspension and for loweringsaid leg and said suspension all independently of said first-namedelevator means.

8. A machine as defined in claim 7 and further characterized in thatcontrol means are provided which operate said primary elevator, saidtransfer means and said' secondary elevator means in ordered and timedsequence such that work is progressively advanced around the machine andgiven a pre-selected sequence of treatments during the circuit of themachine.

9. A machine as claimed in claim 7 and further characterized in thateach said pantograph suspension supports a horizontal, rotatable barreland means are provided around said machine frame for rotating saidbarrel in both immersed and elevated positions in those stationsrequiring barrel rotation.

10. In an automatic machine for the plating and chemical treatment ofmetal articles, which machine has a central frame surrounded by aplurality of separate treating stations, the improvement which comprisesa plurality of individual carriage frames 'mounted for travel aroundsaid machine, a barrel suspension attached to each said carriage frameand extending outwardly therefrom, a horizontal, rotatable barrelattached to each said suspension, a lineshaft mounted along the saidcentral machine frame, a lineshaft spur gear on said lineshaft oppositethose stations requiring barrel rotation, a cam associated with eachsaid lineshaft gear and having a tapered face facing against thedirection of travel of said carriages, a power take-oft" device mountedon each said carriage including a spring-biased, pivotally-mounted gearfor engagement with said cam-faced lineshaft gears and a xedly mountedgear meshing with said spring-biased gear, and means associated witheach said suspension for transmitting rotational power from said ixedlymounted gear to each said barrel.

1l. A machine as claimed in claim l() and further characterized in thatsaid lineshaft extends along each side of the straight-sided length ofsaid machine, and an individual barrel rotation gear drive is providedfor engaging said spring-biased gears in a curved portion of saidmachine.

12. In an automatic machine for plating and chemical treatment, whichmachine has a central frame adapted to be surrounded by a plurality ofseparate treating stations, the improvement which comprises a pluralityof vertical carriage frames mounted for movement around said machine, apantograph suspension pivotally attached to each said carriage frame andextending outwardly therefrom, a

18 lift leg slidably carried by each said carriage frame and pivotallyattached to said suspension at a point outwardly from said carriageframe, an elevator beam suspended from said central frame in a positionto engage said lift legs, elevator means for lifting and lowering saidelevator beam, a conveyor chain attached to said carriages and adaptedto move them around the machine while said suspensions are in anelevated position and control means for operating said elevator meansand said conveyor chain to secure progressive and repeated movement ofsaid carriages around said machine.

13. A machine as claimed in claim l2 and further characterized in that ahorizontal 'Darrel is attached to the outer ends of each said pantographsuspension.

14. An automatic machine for plating and chemical treatment of articlesin bulk, which machine comprises an elongated, central frame, aplurality of treating stations around the outer periphery of said frame,a plurality of individual carriage frames mounted for movement aroundSaid central frame, a pair of upper and a pair of lower pantograph armseach pivotally attached to each said carriage frame and arranged toextend outwardly therefrom over said stations, a barrel hanger armsuspended between such upper and lower pantograph arms to form aparralelogram suspension, a horizontal rotatable barrel attached to saidhanger arms, a lift leg slidably carried on each said carriage frame andhaving its upper end attached to said suspension, an elevator beamsuspended along said central frame opposite stations requiring barrelelevation, said beam being supported from below by a plurality ofinverted T-shaped elevator members slidably suspended from said centralframe, means for lifting and lowering said elevator members, a lineshaftalong the straight-sided portions of said central frame and having spurgears thereon opposite those stations requiring barrel rotation, anindividually-driven barrel rotation gear in a curved end portion of saidframe, an epicyclic gear train on each said carriage for engagement withsaid lineshaft and individual barrel rotation gears, a belt drive andgear train mounted on said pantograph and barrel hanger arms forrotating said barrel, transfer means for advancing said carriages fromone said station to the next said station, a delayed set-down mechanismat those stations requiring shorter immersion times and larger drainagetimes, and control means integrating said elevator means, said transfermeans, and said delayed set-down means to secure progressive movement ofeach barrel around said central frame and through said stations.

15. In an automatic machine for plating and chemical treatment ofarticles, which machine has an elongated, centrally-located framesurrounded by a plurality of separate treating stations, and a pluralityof rotatable barrels mounted for travel through said stations, theimprovement which comprises a lineshaft extending along said centralframe opposite those stations requiring barrel rotation, a spur gear onsaid lineshaft opposite each station requiring barrel rotation, ataper-faced cam on said lineshaft in front of each spur gear and facingin the direction of approach of said barrels, and a spring-loadedpivotally mounted gear in engagement with a xed gear, connected witheach said barrel and its mounting, for engagement of said spring-loadedgear with said cam and lineshaft spur gear, and transmission meansconnecting said fixed gear with said barrel.

References Cited in the le of this patent UNITED STATES PATENTS1,210,853 Schettler Jan. 2, 1917 1,319,872 .Tones et al. Oct. 28, 19192,214,262 Todd Sept. 10, 1940 2,626,621 Curtis Ian. 27, 1953

